I've had a burning plastic smell in my 2010 X for almost a year now. Took it to 2 different local dealers and they had no clue. I decided to check out the xbimmer forum and I do believe user "theonesupreme' has provided a solution. I checked under the hood and the heat shield (plastic divider with weather stripping near the back) was cracked, brittle, with sections missing and lying on a surface that was very hot. I got a little closer to take a sniff and found that it had the exact smell that I've smelled over the past year. I noted the part#'s from previous postings. I'd like to DIY but I need the I just need instructions the 'theonesupreme' provided to a previous user (bmwx5er). I would really appreciate it if you could also provide to me.....if you don't mind.